mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-25 05:34:00 +08:00
231d0aefd8
The "flags" member of "struct wait_queue_t" is used in several places in the kernel code without beeing initialized by init_wait(). "flags" is used in bitwise operations. If "flags" not initialized then unexpected behaviour may take place. Incorrect flags might used later in code. Added initialization of "wait_queue_t.flags" with zero value into "init_wait". Signed-off-by: Evgeny Kuznetsov <EXT-Eugeny.Kuznetsov@nokia.com> [ The bit we care about does end up being initialized by both prepare_to_wait() and add_to_wait_queue(), so this doesn't seem to cause actual bugs, but is definitely the right thing to do -Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
669 lines
21 KiB
C
669 lines
21 KiB
C
#ifndef _LINUX_WAIT_H
|
|
#define _LINUX_WAIT_H
|
|
|
|
#define WNOHANG 0x00000001
|
|
#define WUNTRACED 0x00000002
|
|
#define WSTOPPED WUNTRACED
|
|
#define WEXITED 0x00000004
|
|
#define WCONTINUED 0x00000008
|
|
#define WNOWAIT 0x01000000 /* Don't reap, just poll status. */
|
|
|
|
#define __WNOTHREAD 0x20000000 /* Don't wait on children of other threads in this group */
|
|
#define __WALL 0x40000000 /* Wait on all children, regardless of type */
|
|
#define __WCLONE 0x80000000 /* Wait only on non-SIGCHLD children */
|
|
|
|
/* First argument to waitid: */
|
|
#define P_ALL 0
|
|
#define P_PID 1
|
|
#define P_PGID 2
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#include <linux/list.h>
|
|
#include <linux/stddef.h>
|
|
#include <linux/spinlock.h>
|
|
#include <asm/system.h>
|
|
#include <asm/current.h>
|
|
|
|
typedef struct __wait_queue wait_queue_t;
|
|
typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int flags, void *key);
|
|
int default_wake_function(wait_queue_t *wait, unsigned mode, int flags, void *key);
|
|
|
|
struct __wait_queue {
|
|
unsigned int flags;
|
|
#define WQ_FLAG_EXCLUSIVE 0x01
|
|
void *private;
|
|
wait_queue_func_t func;
|
|
struct list_head task_list;
|
|
};
|
|
|
|
struct wait_bit_key {
|
|
void *flags;
|
|
int bit_nr;
|
|
};
|
|
|
|
struct wait_bit_queue {
|
|
struct wait_bit_key key;
|
|
wait_queue_t wait;
|
|
};
|
|
|
|
struct __wait_queue_head {
|
|
spinlock_t lock;
|
|
struct list_head task_list;
|
|
};
|
|
typedef struct __wait_queue_head wait_queue_head_t;
|
|
|
|
struct task_struct;
|
|
|
|
/*
|
|
* Macros for declaration and initialisaton of the datatypes
|
|
*/
|
|
|
|
#define __WAITQUEUE_INITIALIZER(name, tsk) { \
|
|
.private = tsk, \
|
|
.func = default_wake_function, \
|
|
.task_list = { NULL, NULL } }
|
|
|
|
#define DECLARE_WAITQUEUE(name, tsk) \
|
|
wait_queue_t name = __WAITQUEUE_INITIALIZER(name, tsk)
|
|
|
|
#define __WAIT_QUEUE_HEAD_INITIALIZER(name) { \
|
|
.lock = __SPIN_LOCK_UNLOCKED(name.lock), \
|
|
.task_list = { &(name).task_list, &(name).task_list } }
|
|
|
|
#define DECLARE_WAIT_QUEUE_HEAD(name) \
|
|
wait_queue_head_t name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
|
|
|
|
#define __WAIT_BIT_KEY_INITIALIZER(word, bit) \
|
|
{ .flags = word, .bit_nr = bit, }
|
|
|
|
extern void __init_waitqueue_head(wait_queue_head_t *q, struct lock_class_key *);
|
|
|
|
#define init_waitqueue_head(q) \
|
|
do { \
|
|
static struct lock_class_key __key; \
|
|
\
|
|
__init_waitqueue_head((q), &__key); \
|
|
} while (0)
|
|
|
|
#ifdef CONFIG_LOCKDEP
|
|
# define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \
|
|
({ init_waitqueue_head(&name); name; })
|
|
# define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \
|
|
wait_queue_head_t name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name)
|
|
#else
|
|
# define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name)
|
|
#endif
|
|
|
|
static inline void init_waitqueue_entry(wait_queue_t *q, struct task_struct *p)
|
|
{
|
|
q->flags = 0;
|
|
q->private = p;
|
|
q->func = default_wake_function;
|
|
}
|
|
|
|
static inline void init_waitqueue_func_entry(wait_queue_t *q,
|
|
wait_queue_func_t func)
|
|
{
|
|
q->flags = 0;
|
|
q->private = NULL;
|
|
q->func = func;
|
|
}
|
|
|
|
static inline int waitqueue_active(wait_queue_head_t *q)
|
|
{
|
|
return !list_empty(&q->task_list);
|
|
}
|
|
|
|
extern void add_wait_queue(wait_queue_head_t *q, wait_queue_t *wait);
|
|
extern void add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t *wait);
|
|
extern void remove_wait_queue(wait_queue_head_t *q, wait_queue_t *wait);
|
|
|
|
static inline void __add_wait_queue(wait_queue_head_t *head, wait_queue_t *new)
|
|
{
|
|
list_add(&new->task_list, &head->task_list);
|
|
}
|
|
|
|
/*
|
|
* Used for wake-one threads:
|
|
*/
|
|
static inline void __add_wait_queue_exclusive(wait_queue_head_t *q,
|
|
wait_queue_t *wait)
|
|
{
|
|
wait->flags |= WQ_FLAG_EXCLUSIVE;
|
|
__add_wait_queue(q, wait);
|
|
}
|
|
|
|
static inline void __add_wait_queue_tail(wait_queue_head_t *head,
|
|
wait_queue_t *new)
|
|
{
|
|
list_add_tail(&new->task_list, &head->task_list);
|
|
}
|
|
|
|
static inline void __add_wait_queue_tail_exclusive(wait_queue_head_t *q,
|
|
wait_queue_t *wait)
|
|
{
|
|
wait->flags |= WQ_FLAG_EXCLUSIVE;
|
|
__add_wait_queue_tail(q, wait);
|
|
}
|
|
|
|
static inline void __remove_wait_queue(wait_queue_head_t *head,
|
|
wait_queue_t *old)
|
|
{
|
|
list_del(&old->task_list);
|
|
}
|
|
|
|
void __wake_up(wait_queue_head_t *q, unsigned int mode, int nr, void *key);
|
|
void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key);
|
|
void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, int nr,
|
|
void *key);
|
|
void __wake_up_locked(wait_queue_head_t *q, unsigned int mode);
|
|
void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr);
|
|
void __wake_up_bit(wait_queue_head_t *, void *, int);
|
|
int __wait_on_bit(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned);
|
|
int __wait_on_bit_lock(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned);
|
|
void wake_up_bit(void *, int);
|
|
int out_of_line_wait_on_bit(void *, int, int (*)(void *), unsigned);
|
|
int out_of_line_wait_on_bit_lock(void *, int, int (*)(void *), unsigned);
|
|
wait_queue_head_t *bit_waitqueue(void *, int);
|
|
|
|
#define wake_up(x) __wake_up(x, TASK_NORMAL, 1, NULL)
|
|
#define wake_up_nr(x, nr) __wake_up(x, TASK_NORMAL, nr, NULL)
|
|
#define wake_up_all(x) __wake_up(x, TASK_NORMAL, 0, NULL)
|
|
#define wake_up_locked(x) __wake_up_locked((x), TASK_NORMAL)
|
|
|
|
#define wake_up_interruptible(x) __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
|
|
#define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
|
|
#define wake_up_interruptible_all(x) __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
|
|
#define wake_up_interruptible_sync(x) __wake_up_sync((x), TASK_INTERRUPTIBLE, 1)
|
|
|
|
/*
|
|
* Wakeup macros to be used to report events to the targets.
|
|
*/
|
|
#define wake_up_poll(x, m) \
|
|
__wake_up(x, TASK_NORMAL, 1, (void *) (m))
|
|
#define wake_up_locked_poll(x, m) \
|
|
__wake_up_locked_key((x), TASK_NORMAL, (void *) (m))
|
|
#define wake_up_interruptible_poll(x, m) \
|
|
__wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m))
|
|
#define wake_up_interruptible_sync_poll(x, m) \
|
|
__wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m))
|
|
|
|
#define __wait_event(wq, condition) \
|
|
do { \
|
|
DEFINE_WAIT(__wait); \
|
|
\
|
|
for (;;) { \
|
|
prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
|
|
if (condition) \
|
|
break; \
|
|
schedule(); \
|
|
} \
|
|
finish_wait(&wq, &__wait); \
|
|
} while (0)
|
|
|
|
/**
|
|
* wait_event - sleep until a condition gets true
|
|
* @wq: the waitqueue to wait on
|
|
* @condition: a C expression for the event to wait for
|
|
*
|
|
* The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
|
|
* @condition evaluates to true. The @condition is checked each time
|
|
* the waitqueue @wq is woken up.
|
|
*
|
|
* wake_up() has to be called after changing any variable that could
|
|
* change the result of the wait condition.
|
|
*/
|
|
#define wait_event(wq, condition) \
|
|
do { \
|
|
if (condition) \
|
|
break; \
|
|
__wait_event(wq, condition); \
|
|
} while (0)
|
|
|
|
#define __wait_event_timeout(wq, condition, ret) \
|
|
do { \
|
|
DEFINE_WAIT(__wait); \
|
|
\
|
|
for (;;) { \
|
|
prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
|
|
if (condition) \
|
|
break; \
|
|
ret = schedule_timeout(ret); \
|
|
if (!ret) \
|
|
break; \
|
|
} \
|
|
finish_wait(&wq, &__wait); \
|
|
} while (0)
|
|
|
|
/**
|
|
* wait_event_timeout - sleep until a condition gets true or a timeout elapses
|
|
* @wq: the waitqueue to wait on
|
|
* @condition: a C expression for the event to wait for
|
|
* @timeout: timeout, in jiffies
|
|
*
|
|
* The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
|
|
* @condition evaluates to true. The @condition is checked each time
|
|
* the waitqueue @wq is woken up.
|
|
*
|
|
* wake_up() has to be called after changing any variable that could
|
|
* change the result of the wait condition.
|
|
*
|
|
* The function returns 0 if the @timeout elapsed, and the remaining
|
|
* jiffies if the condition evaluated to true before the timeout elapsed.
|
|
*/
|
|
#define wait_event_timeout(wq, condition, timeout) \
|
|
({ \
|
|
long __ret = timeout; \
|
|
if (!(condition)) \
|
|
__wait_event_timeout(wq, condition, __ret); \
|
|
__ret; \
|
|
})
|
|
|
|
#define __wait_event_interruptible(wq, condition, ret) \
|
|
do { \
|
|
DEFINE_WAIT(__wait); \
|
|
\
|
|
for (;;) { \
|
|
prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
|
|
if (condition) \
|
|
break; \
|
|
if (!signal_pending(current)) { \
|
|
schedule(); \
|
|
continue; \
|
|
} \
|
|
ret = -ERESTARTSYS; \
|
|
break; \
|
|
} \
|
|
finish_wait(&wq, &__wait); \
|
|
} while (0)
|
|
|
|
/**
|
|
* wait_event_interruptible - sleep until a condition gets true
|
|
* @wq: the waitqueue to wait on
|
|
* @condition: a C expression for the event to wait for
|
|
*
|
|
* The process is put to sleep (TASK_INTERRUPTIBLE) until the
|
|
* @condition evaluates to true or a signal is received.
|
|
* The @condition is checked each time the waitqueue @wq is woken up.
|
|
*
|
|
* wake_up() has to be called after changing any variable that could
|
|
* change the result of the wait condition.
|
|
*
|
|
* The function will return -ERESTARTSYS if it was interrupted by a
|
|
* signal and 0 if @condition evaluated to true.
|
|
*/
|
|
#define wait_event_interruptible(wq, condition) \
|
|
({ \
|
|
int __ret = 0; \
|
|
if (!(condition)) \
|
|
__wait_event_interruptible(wq, condition, __ret); \
|
|
__ret; \
|
|
})
|
|
|
|
#define __wait_event_interruptible_timeout(wq, condition, ret) \
|
|
do { \
|
|
DEFINE_WAIT(__wait); \
|
|
\
|
|
for (;;) { \
|
|
prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
|
|
if (condition) \
|
|
break; \
|
|
if (!signal_pending(current)) { \
|
|
ret = schedule_timeout(ret); \
|
|
if (!ret) \
|
|
break; \
|
|
continue; \
|
|
} \
|
|
ret = -ERESTARTSYS; \
|
|
break; \
|
|
} \
|
|
finish_wait(&wq, &__wait); \
|
|
} while (0)
|
|
|
|
/**
|
|
* wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses
|
|
* @wq: the waitqueue to wait on
|
|
* @condition: a C expression for the event to wait for
|
|
* @timeout: timeout, in jiffies
|
|
*
|
|
* The process is put to sleep (TASK_INTERRUPTIBLE) until the
|
|
* @condition evaluates to true or a signal is received.
|
|
* The @condition is checked each time the waitqueue @wq is woken up.
|
|
*
|
|
* wake_up() has to be called after changing any variable that could
|
|
* change the result of the wait condition.
|
|
*
|
|
* The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it
|
|
* was interrupted by a signal, and the remaining jiffies otherwise
|
|
* if the condition evaluated to true before the timeout elapsed.
|
|
*/
|
|
#define wait_event_interruptible_timeout(wq, condition, timeout) \
|
|
({ \
|
|
long __ret = timeout; \
|
|
if (!(condition)) \
|
|
__wait_event_interruptible_timeout(wq, condition, __ret); \
|
|
__ret; \
|
|
})
|
|
|
|
#define __wait_event_interruptible_exclusive(wq, condition, ret) \
|
|
do { \
|
|
DEFINE_WAIT(__wait); \
|
|
\
|
|
for (;;) { \
|
|
prepare_to_wait_exclusive(&wq, &__wait, \
|
|
TASK_INTERRUPTIBLE); \
|
|
if (condition) { \
|
|
finish_wait(&wq, &__wait); \
|
|
break; \
|
|
} \
|
|
if (!signal_pending(current)) { \
|
|
schedule(); \
|
|
continue; \
|
|
} \
|
|
ret = -ERESTARTSYS; \
|
|
abort_exclusive_wait(&wq, &__wait, \
|
|
TASK_INTERRUPTIBLE, NULL); \
|
|
break; \
|
|
} \
|
|
} while (0)
|
|
|
|
#define wait_event_interruptible_exclusive(wq, condition) \
|
|
({ \
|
|
int __ret = 0; \
|
|
if (!(condition)) \
|
|
__wait_event_interruptible_exclusive(wq, condition, __ret);\
|
|
__ret; \
|
|
})
|
|
|
|
|
|
#define __wait_event_interruptible_locked(wq, condition, exclusive, irq) \
|
|
({ \
|
|
int __ret = 0; \
|
|
DEFINE_WAIT(__wait); \
|
|
if (exclusive) \
|
|
__wait.flags |= WQ_FLAG_EXCLUSIVE; \
|
|
do { \
|
|
if (likely(list_empty(&__wait.task_list))) \
|
|
__add_wait_queue_tail(&(wq), &__wait); \
|
|
set_current_state(TASK_INTERRUPTIBLE); \
|
|
if (signal_pending(current)) { \
|
|
__ret = -ERESTARTSYS; \
|
|
break; \
|
|
} \
|
|
if (irq) \
|
|
spin_unlock_irq(&(wq).lock); \
|
|
else \
|
|
spin_unlock(&(wq).lock); \
|
|
schedule(); \
|
|
if (irq) \
|
|
spin_lock_irq(&(wq).lock); \
|
|
else \
|
|
spin_lock(&(wq).lock); \
|
|
} while (!(condition)); \
|
|
__remove_wait_queue(&(wq), &__wait); \
|
|
__set_current_state(TASK_RUNNING); \
|
|
__ret; \
|
|
})
|
|
|
|
|
|
/**
|
|
* wait_event_interruptible_locked - sleep until a condition gets true
|
|
* @wq: the waitqueue to wait on
|
|
* @condition: a C expression for the event to wait for
|
|
*
|
|
* The process is put to sleep (TASK_INTERRUPTIBLE) until the
|
|
* @condition evaluates to true or a signal is received.
|
|
* The @condition is checked each time the waitqueue @wq is woken up.
|
|
*
|
|
* It must be called with wq.lock being held. This spinlock is
|
|
* unlocked while sleeping but @condition testing is done while lock
|
|
* is held and when this macro exits the lock is held.
|
|
*
|
|
* The lock is locked/unlocked using spin_lock()/spin_unlock()
|
|
* functions which must match the way they are locked/unlocked outside
|
|
* of this macro.
|
|
*
|
|
* wake_up_locked() has to be called after changing any variable that could
|
|
* change the result of the wait condition.
|
|
*
|
|
* The function will return -ERESTARTSYS if it was interrupted by a
|
|
* signal and 0 if @condition evaluated to true.
|
|
*/
|
|
#define wait_event_interruptible_locked(wq, condition) \
|
|
((condition) \
|
|
? 0 : __wait_event_interruptible_locked(wq, condition, 0, 0))
|
|
|
|
/**
|
|
* wait_event_interruptible_locked_irq - sleep until a condition gets true
|
|
* @wq: the waitqueue to wait on
|
|
* @condition: a C expression for the event to wait for
|
|
*
|
|
* The process is put to sleep (TASK_INTERRUPTIBLE) until the
|
|
* @condition evaluates to true or a signal is received.
|
|
* The @condition is checked each time the waitqueue @wq is woken up.
|
|
*
|
|
* It must be called with wq.lock being held. This spinlock is
|
|
* unlocked while sleeping but @condition testing is done while lock
|
|
* is held and when this macro exits the lock is held.
|
|
*
|
|
* The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq()
|
|
* functions which must match the way they are locked/unlocked outside
|
|
* of this macro.
|
|
*
|
|
* wake_up_locked() has to be called after changing any variable that could
|
|
* change the result of the wait condition.
|
|
*
|
|
* The function will return -ERESTARTSYS if it was interrupted by a
|
|
* signal and 0 if @condition evaluated to true.
|
|
*/
|
|
#define wait_event_interruptible_locked_irq(wq, condition) \
|
|
((condition) \
|
|
? 0 : __wait_event_interruptible_locked(wq, condition, 0, 1))
|
|
|
|
/**
|
|
* wait_event_interruptible_exclusive_locked - sleep exclusively until a condition gets true
|
|
* @wq: the waitqueue to wait on
|
|
* @condition: a C expression for the event to wait for
|
|
*
|
|
* The process is put to sleep (TASK_INTERRUPTIBLE) until the
|
|
* @condition evaluates to true or a signal is received.
|
|
* The @condition is checked each time the waitqueue @wq is woken up.
|
|
*
|
|
* It must be called with wq.lock being held. This spinlock is
|
|
* unlocked while sleeping but @condition testing is done while lock
|
|
* is held and when this macro exits the lock is held.
|
|
*
|
|
* The lock is locked/unlocked using spin_lock()/spin_unlock()
|
|
* functions which must match the way they are locked/unlocked outside
|
|
* of this macro.
|
|
*
|
|
* The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
|
|
* set thus when other process waits process on the list if this
|
|
* process is awaken further processes are not considered.
|
|
*
|
|
* wake_up_locked() has to be called after changing any variable that could
|
|
* change the result of the wait condition.
|
|
*
|
|
* The function will return -ERESTARTSYS if it was interrupted by a
|
|
* signal and 0 if @condition evaluated to true.
|
|
*/
|
|
#define wait_event_interruptible_exclusive_locked(wq, condition) \
|
|
((condition) \
|
|
? 0 : __wait_event_interruptible_locked(wq, condition, 1, 0))
|
|
|
|
/**
|
|
* wait_event_interruptible_exclusive_locked_irq - sleep until a condition gets true
|
|
* @wq: the waitqueue to wait on
|
|
* @condition: a C expression for the event to wait for
|
|
*
|
|
* The process is put to sleep (TASK_INTERRUPTIBLE) until the
|
|
* @condition evaluates to true or a signal is received.
|
|
* The @condition is checked each time the waitqueue @wq is woken up.
|
|
*
|
|
* It must be called with wq.lock being held. This spinlock is
|
|
* unlocked while sleeping but @condition testing is done while lock
|
|
* is held and when this macro exits the lock is held.
|
|
*
|
|
* The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq()
|
|
* functions which must match the way they are locked/unlocked outside
|
|
* of this macro.
|
|
*
|
|
* The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
|
|
* set thus when other process waits process on the list if this
|
|
* process is awaken further processes are not considered.
|
|
*
|
|
* wake_up_locked() has to be called after changing any variable that could
|
|
* change the result of the wait condition.
|
|
*
|
|
* The function will return -ERESTARTSYS if it was interrupted by a
|
|
* signal and 0 if @condition evaluated to true.
|
|
*/
|
|
#define wait_event_interruptible_exclusive_locked_irq(wq, condition) \
|
|
((condition) \
|
|
? 0 : __wait_event_interruptible_locked(wq, condition, 1, 1))
|
|
|
|
|
|
|
|
#define __wait_event_killable(wq, condition, ret) \
|
|
do { \
|
|
DEFINE_WAIT(__wait); \
|
|
\
|
|
for (;;) { \
|
|
prepare_to_wait(&wq, &__wait, TASK_KILLABLE); \
|
|
if (condition) \
|
|
break; \
|
|
if (!fatal_signal_pending(current)) { \
|
|
schedule(); \
|
|
continue; \
|
|
} \
|
|
ret = -ERESTARTSYS; \
|
|
break; \
|
|
} \
|
|
finish_wait(&wq, &__wait); \
|
|
} while (0)
|
|
|
|
/**
|
|
* wait_event_killable - sleep until a condition gets true
|
|
* @wq: the waitqueue to wait on
|
|
* @condition: a C expression for the event to wait for
|
|
*
|
|
* The process is put to sleep (TASK_KILLABLE) until the
|
|
* @condition evaluates to true or a signal is received.
|
|
* The @condition is checked each time the waitqueue @wq is woken up.
|
|
*
|
|
* wake_up() has to be called after changing any variable that could
|
|
* change the result of the wait condition.
|
|
*
|
|
* The function will return -ERESTARTSYS if it was interrupted by a
|
|
* signal and 0 if @condition evaluated to true.
|
|
*/
|
|
#define wait_event_killable(wq, condition) \
|
|
({ \
|
|
int __ret = 0; \
|
|
if (!(condition)) \
|
|
__wait_event_killable(wq, condition, __ret); \
|
|
__ret; \
|
|
})
|
|
|
|
/*
|
|
* These are the old interfaces to sleep waiting for an event.
|
|
* They are racy. DO NOT use them, use the wait_event* interfaces above.
|
|
* We plan to remove these interfaces.
|
|
*/
|
|
extern void sleep_on(wait_queue_head_t *q);
|
|
extern long sleep_on_timeout(wait_queue_head_t *q,
|
|
signed long timeout);
|
|
extern void interruptible_sleep_on(wait_queue_head_t *q);
|
|
extern long interruptible_sleep_on_timeout(wait_queue_head_t *q,
|
|
signed long timeout);
|
|
|
|
/*
|
|
* Waitqueues which are removed from the waitqueue_head at wakeup time
|
|
*/
|
|
void prepare_to_wait(wait_queue_head_t *q, wait_queue_t *wait, int state);
|
|
void prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state);
|
|
void finish_wait(wait_queue_head_t *q, wait_queue_t *wait);
|
|
void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait,
|
|
unsigned int mode, void *key);
|
|
int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
|
|
int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
|
|
|
|
#define DEFINE_WAIT_FUNC(name, function) \
|
|
wait_queue_t name = { \
|
|
.private = current, \
|
|
.func = function, \
|
|
.task_list = LIST_HEAD_INIT((name).task_list), \
|
|
}
|
|
|
|
#define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function)
|
|
|
|
#define DEFINE_WAIT_BIT(name, word, bit) \
|
|
struct wait_bit_queue name = { \
|
|
.key = __WAIT_BIT_KEY_INITIALIZER(word, bit), \
|
|
.wait = { \
|
|
.private = current, \
|
|
.func = wake_bit_function, \
|
|
.task_list = \
|
|
LIST_HEAD_INIT((name).wait.task_list), \
|
|
}, \
|
|
}
|
|
|
|
#define init_wait(wait) \
|
|
do { \
|
|
(wait)->private = current; \
|
|
(wait)->func = autoremove_wake_function; \
|
|
INIT_LIST_HEAD(&(wait)->task_list); \
|
|
(wait)->flags = 0; \
|
|
} while (0)
|
|
|
|
/**
|
|
* wait_on_bit - wait for a bit to be cleared
|
|
* @word: the word being waited on, a kernel virtual address
|
|
* @bit: the bit of the word being waited on
|
|
* @action: the function used to sleep, which may take special actions
|
|
* @mode: the task state to sleep in
|
|
*
|
|
* There is a standard hashed waitqueue table for generic use. This
|
|
* is the part of the hashtable's accessor API that waits on a bit.
|
|
* For instance, if one were to have waiters on a bitflag, one would
|
|
* call wait_on_bit() in threads waiting for the bit to clear.
|
|
* One uses wait_on_bit() where one is waiting for the bit to clear,
|
|
* but has no intention of setting it.
|
|
*/
|
|
static inline int wait_on_bit(void *word, int bit,
|
|
int (*action)(void *), unsigned mode)
|
|
{
|
|
if (!test_bit(bit, word))
|
|
return 0;
|
|
return out_of_line_wait_on_bit(word, bit, action, mode);
|
|
}
|
|
|
|
/**
|
|
* wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it
|
|
* @word: the word being waited on, a kernel virtual address
|
|
* @bit: the bit of the word being waited on
|
|
* @action: the function used to sleep, which may take special actions
|
|
* @mode: the task state to sleep in
|
|
*
|
|
* There is a standard hashed waitqueue table for generic use. This
|
|
* is the part of the hashtable's accessor API that waits on a bit
|
|
* when one intends to set it, for instance, trying to lock bitflags.
|
|
* For instance, if one were to have waiters trying to set bitflag
|
|
* and waiting for it to clear before setting it, one would call
|
|
* wait_on_bit() in threads waiting to be able to set the bit.
|
|
* One uses wait_on_bit_lock() where one is waiting for the bit to
|
|
* clear with the intention of setting it, and when done, clearing it.
|
|
*/
|
|
static inline int wait_on_bit_lock(void *word, int bit,
|
|
int (*action)(void *), unsigned mode)
|
|
{
|
|
if (!test_and_set_bit(bit, word))
|
|
return 0;
|
|
return out_of_line_wait_on_bit_lock(word, bit, action, mode);
|
|
}
|
|
|
|
#endif /* __KERNEL__ */
|
|
|
|
#endif
|